/*
* Copyright (c) 2000-2004 Apple Computer, Inc. All Rights Reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this
* file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
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* @APPLE_LICENSE_HEADER_END@
*///
// bufferfifo - a Sink that queues data in a FIFO of buffers for retrieval
//
#include"bufferfifo.h"
#include<security_utilities/memutils.h>
namespace Security {
//
// On destruction, throw away all queued buffers (that haven't been picked up)
//
BufferFifo::~BufferFifo()
{
while (!mBuffers.empty()) {
delete mBuffers.front();
mBuffers.pop();
}
}
voidBufferFifo::clearBuffer()
{
while (!mBuffers.empty()) {
delete mBuffers.front();
mBuffers.pop();
}
mSize = 0;
}
//
// This is the put function of a Sink. We store the data in at most two buffers:
// First we append to the last (partially filled) one; then we allocate a new one
// (if needed) to hold the rest.
//
voidBufferFifo::consume(constvoid *data, size_t size)
{
mSize += size;
// step 1: fill the rearmost (partially filled) buffer
if (size > 0 && !mBuffers.empty()) {
Buffer *current = mBuffers.back();
size_t length = current->put(data, size);
data = LowLevelMemoryUtilities::increment(data, length);
size -= length;
}
// step 2: if there's anything left, make a new buffer and fill it
if (size > 0) { // not done
Buffer *current = new Buffer(max(bufferLength, size));
mBuffers.push(current);
assert(current->available() >= size);
current->put(data, size);
}
}
//
// Pull the first (FI) buffer off the queue and deliver it.
// We retain no memory of it; it belongs to the caller now.
//
Buffer *BufferFifo::pop()
{
assert(!mBuffers.empty());
Buffer *top = mBuffers.front();
mBuffers.pop();
return top;
}
} // end namespace Security